Apparatus for changing the pitch of drums

ABSTRACT

An apparatus for changing the pitch of drums, comprising a source of compressed gas, a container for holding said compressed gas at a constant pressure and valve means for selectively conducting said pressurized gas into drums, and selectively releasing pressurized gas from said drums, the drums being raised in pitch when pressurized. Also means for independently adjusting the pitch to which each drum may be raised.

United States Patent (72] Inventors Scott Cannes [56] References CitedEast Aurora; UNITED STATES PATENTS RkhmlfiflMlmfimMWX- 635,192 10/1899Sapp 84/411 I211 P 1,054,009 2/1913 Ludwig 84/419 [22] FM FOREIGNPATENTS [45} Patented July 6, 197! 73 Assignee M D system I 589,6176/l947 Great Brltaln 84/41 1 o my 432,206 9/1967 Switzerland 84/411Primary Examiner- Richard B. Wilkinson A. :iant Examiner- Lawrence R.Franklin Auomey- Kegan, Kegan and Berkman ABSTRACT: An apparatus forchanging the pitch of drums, [54] APPARSATUS FOR CHANGING ml: PITCH OFcomprising a source of compressed gas, a container for hold- DRUM 2D ining said compressed gas at a constant pressure and valve aching g meansfor selectively conducting said pressurized gas into [52] U.S.Cl.84/411, drums, and selectively releasing pressurized gas from said 84/419 drums, the drums being raised in pitch when pressurized. Also [51]Int. Cl ..Gl0d 13/02 means for independently adjusting the pitch towhich each [50] Field of Search 84/41 1, 419 drum may be raised.

/.9 20 36 34 sAucEV. Am I 62 24 PRESSURE PEDAL ACCUMULATOR VALVE 22 I Iv v 58 ,26 I? REL A R /6 300 30b 30c COMPRESSOR 33a 33b 330 r 30a 30b30c SWITCH APPARATUS FOR CHANGING THE PITCH OF DRUMS This applicationrelates to means for selectively raising and lowering the pitch or toneof drums used by musicians. More specifically it relates to an apparatusfor pressurizing and depressurizing a set of drums by actuating a footpedal which controls a supply of compressed air or other gas which isdelivered to the interior of the drums.

The desirability of instantaneously changing the pitch of one or moredrums in known to musicians. Unusual and novel percussion sounds may beplayed without the necessity of having a multiplicity of drumspermanently tuned to different pitches, so as to be available to rendera sound of a given pitch at a desired moment in a piece of music.

Various techniques for increasing the air pressure in a drum to vary thepitch of its sound are known in the prior art. Swiss Pat. No. 432,206teaches a technique of increasing the air pressure by means of a footdepressed rubber sack connected through a conduit to an opening in thewall of the drum. Other means for introducing the air are bellows, and afoot operated piston pump. None of these prior art devices issatisfactory in that the air pressure cannot be raised instantaneously,and cannot be maintained in the drum for as long as desired. Moreoverthe prior art devices require excessive physical ex ertion by thedrummer, and even then cannot provide sufficient pressure to raise thepitch of a drum appreciably. In addition, the prior art devices cannotbe preadjusted to raise the drum to an exact pitch, the pitch achievedbeing dependent on the skill of the drummer.

' It is an object of this invention to provide an apparatus whereby oneor more drums may be instantaneously raised in pitch by up to twooctaves, maintained at the raised pitch as long as required by themusical piece, and instantaneously returned to the original'pitch.Conversely, one or more drums may be maintained at a high pitch, andinstantaneously lowered in pitch.

Another object of this invention is to provide an apparatus for raisingthe pitch of a drum to any of a plurality of preselected notes.

An important feature of this invention enables a drummer to raiseinstantly the pitch of a drum for a duration of as short as one beat,and to instantly return the drum to its original pitch.

An additional feature of the invention permits separate tuning of eachdrum so that a plurality of drums may be raised in pitch in unison, orto separate preselected notes.

Another feature of one embodiment of the invention enables a drummer tointroduce unusual percussion sounds by pressurized a drum withlighter-than-air gases.

These and other objects and features of the invention will becomeapparent from a reading of the specification in conjunction with thedrawings, wherein FIGURE 1 is a schematic representation of thecompressor, the gas storage and control system, and the drums.

FIGURE 2 is a vertical cross sectional view valve of the apparatus.

Referring more specifically to the drawings, there is shown in FIGURE 1a motor-driven air compressor 8 which is powered by a source of electriccurrent 10. The compressor draws in air through an air filter 12. Apressure-actuated switch 14 controlling electric power for thecompressor is pneumatically connected through conduit 16 to thecompressed air pipe 18 leading from the compressor. The switch 14 isresponsive to pressure in the pipe 18 to turn the compressor 8 on andoff at times required to maintain a preset pressure. The compressed airis stored in an air pressure accumulator 20 or container which may beany type of tank commonly used for holding compressed air. A pressuregauge 19 in the pipe 18 provides a visual indication of the amount ofpressure in the pipe 18 and the air pressure accumulator 20. A

of the pedal safety valve or pressure relief valve 22 having aselectable pressure release point of up to 150 pounds per square inch isalso connected to the pipe 18. A pedal valve 24 described below isconnected to the air pressure accumulator 20 so as to pennit airpressure from the accumulator 20 to flow through a duct 26 into amanifold 28 to which are connected by hoses 30a, 30b, and 300, drums32a, 32b and 32c. A pedal having a return spring 36 actuates said pedalvalve 24 so that when the pedal 34 is depressed, air pressure from thepressure container 20 is permitted to flow into the drums 32a, 32b and320. When the pedal 34 is released, it is raised by the return spring36, and the pedal valve 24 releases air pressure from the drums into theatmosphere. A set of adjustable pressure valves or regulators 33a 33band 330 are installed in hoses 30a, 30b and 300, as is shown inFIGURE 1. The adjustable pressure valves may be preset individually topermit pressurizing gas to flow into each drum at a selectable pressure.In this manner, the pitch to which each drum may be raised isindividually selectable.

Referring more specifically to FIG. 2, there is shown a vertical crosssection of the pedal valve 24, comprising a cylinder 38 and a piston 40adapted to slide within said cylinder. An inlet duct 42 is bored in thecylinder 38 to provide an air conduit from the air pressure accumulator20 to the inner surface of the cylinder wall 44. Similarly, an outletduct 46 provides an air conduit from the cylinder wall to the manifold28. The outlet duct 46 opens in the cylinder wall 44 at a point 48directly opposite and higher than the cylinder wall opening for theinlet duct 50. An air pressure port 52 is bored through the piston 40 atan angle so that when the piston 40 is lowered in the cylinder 26, theair pressure port connects the inlet duct 42 with the outlet duct 46,allowing pressurized air to flow into the manifold 28 and into thedrums. A venting port 54 is bored in said piston 40, opening in the wallof the piston at a point directly below the air pressure port 52, andopening in the face 56 of the piston. A venting duct 58 bored in thecylinder head 60 connects the cylinder interior with the atmosphere. Inoperation, the pedal 34 is depressed, and said movement is transmittedto the piston 40 by means of a stem 62 attached to the piston. Thepiston 40 slides downwardly so that the inlet duct 42 is connected withthe outlet duct 46 by means of the air pressure port 52, allowingpressurized air to flow into the manifold 28 and into the drums 32a,32b, and 320. When the pedal 34 is released, the piston 40 is liftedupward by means of the spring 36, the air pressure port 52 isdisconnected from the inlet and outlet ducts 42 and 46, and the ventingduct 54 is raised to a position where it connects with the outlet duct46. Air under pressure in the drums 32a, 32b and 320 flows through themanifold 28, the outlet duct 46, the venting port 54, and thecylinderinterior 62, and is released into the atmosphere through the ventingduct 58. Thus, by stepping down on the pedal 34, a drummer mayinstantaneously pressurize the set of drums, and by releasing the pedal,the drums are instantaneously returned to atmospheric pressure.

In the embodiment of the invention described above, the safety reliefvalve is set to open at a pressure of pounds per square inch. Thepressure controlled switch 14 is set to actuate the compressor 8 whenthe air pressure in the pipe 18 drops to 50 pounds per square inch, andto turn it off when the pressure reaches 70 pounds per square inch. Thehoses 30a, 30b and 30c connect the manifold 28a to the drums 32a, 32band 320 by means of flare connections set in the vent openings alreadyexisting in the drums. When the interior air pressure of a drum ischanged the resulting change in pitch is proportional to the square rootof the total pressure times the square root of the original tension.

Another embodiment of the invention utilizes helium or another light gasrather than air as the pressurizing gas. This is readily accomplished bysubstituting a bottle of compressed gas such as helium in place of theair compressor 8 and the switch 14. A bottle of compressed air may alsobe used in place of the compressor and switch. The use of helium oranother lighter-than-air gas has two effects on the drum: First, thepitch is higher than with air, other factors being equal, and the rateof change of pitch with respect to pressure is greater being struck, andsounds for a longer time.

While this invention has been described in connection with a' preferredembodiment, it is to be understood that the description is illustrativeonly and is not intended to limit the invention, the scope of which isdefined by the appended claim.

What we claim is:

1. An apparatus for selectively varying the pitch of a drum, saidapparatus comprising:

a chamber for holding gas at a selected pressure;

means for maintaining gas in said chamber at said selected pressure;

a drum;

conduit means for conducting pressurized gas between said chamber andsaid drum;

valve means in said conduit means, said valve means'selectively operableto pass pressurized gas through said conduit means into said drum, andselectively to release pressurized gas from said drum.

2. The apparatus set forth in claim 1 wherein said means for maintaininggas in said chamber at said selected pressure is a mechanical aircompressor.

3. The apparatus set forth in claim 1 wherein said means for maintaininggas in said chamber at said selected pressure is a container ofcompressed gas.

4. The apparatus set forth in claim 3 wherein said compressed gas ishelium.

5. The apparatus set forth in claim 1 wherein said valve means is a footoperated valve.

6. The apparatus set forth in claim 1 wherein said valve means comprisesan inlet duct connected to said chamber for holding gas under pressure,and outlet duct connected to said drum, and a venting duct; and

shiftable port means movable to selectively connect said inlet duct withsaid outlet duct to permit pressurized gas to flow into said drum, andto alternatively connect said outlet duct with said venting duct topermit pressurized gas to flow out of saiddrum.

7. The apparatus set forth in claim 6, and further comprising foot pedalmeans for shifting said port means to connect said inlet duct with saidoutlet duct, and return spring means for shifting said portto connectsaid outlet duct with said venting duct.

8. The apparatus set forth in claim 1, and further comprising aplurality of conduit means for conducting pressurized gas to a pluralityof drums;

each of said conduit means having an independently adjustable gaspressure regulator to enable independent adjustment of pressuredelivered to each drum,

whereby the pitch to which each drum may be raised is independentlyadjustable.

1. An apparatus for selectively varying the pitch of a drum, saidapparatus comprising: a chamber for holding gas at a selected pressure;means for maintaining gas in said chamber at said selected pressure; adrum; conduit means for conducting pressurized gas between said chamberand said drum; valve means in said conduit means, said valve meansselectively operable to pass pressurized gas through said conduit meansinto said drum, and selectively to release pressurized gas from saiddrum.
 2. The apparatus set forth in claim 1 wherein said means formaintaining gas in said chamber at said selected pressure is amechanical air compressor.
 3. The apparatus set forth in claim 1 whereinsaid means for maintaining gas in said chamber at said selected pressureis a container of compressed gas.
 4. The apparatus set forth in claim 3wherein said compressed gas is helium.
 5. The apparatus set forth inclaim 1 wherein said valve means is a foot operated valve.
 6. Theapparatus set forth in claim 1 wherein said valve means comprises aninlet duct connected to said chamber for holding gas under pressure, andoutlet duct connected to said drum, and a venting duct; and shiftableport means movable to selectively connect said inlet duct with saidoutlet duct to permit pressurized gas to flow into said drum, and toalternatively connect said outlet duct with said venting duct to permitpressurized gas to flow out of said drum.
 7. The apparatus set forth inclaim 6, and further comprising foot pedal means for shifting said portmeans to connect said inlet duct with said outlet duct, and returnspring means for shifting said port to connect said outlet duct withsaid venting duct.
 8. The apparatus set forth in claim 1, and furthercomprising a plurality of conduit means for conducting pressurized gasto a plurality of drums; each of said conduit means having anindependently adjustable gas pressure regulator to enable independentadjustment of pressuRe delivered to each drum, whereby the pitch towhich each drum may be raised is independently adjustable.